Method of making bearings



Aug. 6, 1940. R s s 2,210,132

' METHOD OF MAKING BEARINGS Original F iled March 51, 1937 Q) v F w a Z ;Z" T

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ATTO R N EYS Patented Aug. 6,1940

METHOD: OF MAKING BEARINGS Raymond B. Searles, New Britain, Conm, assignor to The Fafnir Bearing Company, New Britain, Connlg'a corporation of Connecticut Original application March31, 1937, Serial No. 134,130,110w Patent No. 2,'16 2,977,dated June 20, 1939. Divided and this application August 6, 1937,, Serial No. 157,650;

2 Claims. (01. 29 14s.4).

My invention relates to an anti-friction bearing and more particularly to means for holding such a bearing on a shaft or the like. This application 'is a division of my application, Serial No. 134,130, filed March 31, 1937, issuedJune 20, 1939 asPatent No. 2,162,977; '{I-Ieretofore inner. bearing rings have beenheld on, shafts by various 'means including shoulders and nuts, adapter sleeves interposed between the bore of thering andj theshaftQlocking collars engaging the ring, etc. Innerrings have-also frequently been held on shafts, by means of :a press fitb fThe usual pressfit isnot ordinarily adapted for bearings 'which are t'obe slid alongia shaft and located at'some position thereonQin the field. vIn other words, press fits are usually employed where "assemblies maybe made on the bench.- 1 Allfof the othejr methods'of holding inner rings mentionedabove involvef atleast one otherpart in addition to the inner ring. j

'It is an'object of" the invention to provide an improved method ofrforming 'a'n anti-friction bearing ring with means integral therewith and forming a 'part'thereof and acting by reason of the inherent resiliency of t-herlng for'h'olding the samein place and yet which may be very readilyapplied.

In general the object is to provide an improved,

simple method of forming means for securely holding a bearing ring in place.

In the drawing which shows, for illustrative purpose only, a preferred form of the invention Fig. 1 is a central sectional view through a pillow block-and shaft, illustrating my improved bearing in place; I

Figs. 2, 3 and 4 are sectional views of a ring and illustrate parts of three steps in one method of manufacture of my improved bearing holding means;

Fig. 5 is a sectional view through an inner ring not under stress and embodying my invention; and

Fig. 6 is a sectional view through the inner ring shown in Fig. 1, that is, illustrating the ring of Fig. 5 applied to a shaft.

In said drawing 5 indicates any conventional or desirable type of bearing box or pillow block, illustrated here merely for the purpose of showing a complete bearing application. An outer bearing ring 6 is seated in the box 5. A long inner ring I is carried by the shaft 8v and antifriction bearing members, such as balls 9, are interposed between the inner and outer rings and, in the form shown, run in grooved raceways in both rings. My invention relates particularly to a method for providing means for holding the inner ring Ton the-shaft 8.

Briefly stated-the invention in a broad sense may be said to consist in'providing the ringwith made so by slitting the'ring. "As illustratedin 'Figsf l 'and5,the inner ring is providedwith a pair of diametrically opposite'slots' [2-43, ex-

tending inwardly from the edge of 3 the ring and terminating in"'r0unded" or filleted' ends M; to

avoid cracking. It will be seen that the righthand end of the ring 1 is expansible and by means of any suitabletype of tool or wedge thebore l l may beexpandedtand the entire'ring slid along on the"s'haft*-'8':to the desiredposition and the expanding tool"or"wedge'thenremoved, so as to permit the inherent resiliency of the ring 1 to tightly contract the bore ll onto the shaft 8. The extent of the holding force depends upon several factors, including the thickness and degree of resiliency of the inner ring, the point or area of contact between the bore H and the shaft, and its distance from the nominal fulcrum about which the bore H expands, as well as the extent of normal contraction of the ring when not under stress. These, however, are all design factors, which will be readily understood by those skilled in the art.

While the ring I may be formed in a number of ways and substantially the same results obtained, in Figs. 2, 3 and 4 I have illustrated a preferred novel method of forming the inner.

ring which is simple, practical and in conformity with present bearing manufacturing practice. The ring I, as shown in Fig. 2, is first formed by usual machining methods, so that the entire bore is of uniform diameter and less than the diameter of the shaft which ultimately it is to fit. The ring is slotted, as heretofore described. The ring then goes through the usual hardening process and is then ready to be ground. The raceway groove and the outer diameter may be ground by the usual methods. The expansible end of the ring is expanded by any suitable means; such as a wedge I6, forced into a slot. A wedge in the form of a ball may, in practice, be an effective and readily insertible type of wedge. With the ring expanded, as shown in Fig. 3,-the ring is subjected to the usual bore grinding process and the bore ground outto the desired uniform diameter while the expansible end remains expanded. The ring, after being bore ground, will appear as in Fig. 4 and the diameter of the bore then is the diameter H], as appears in Fig. 5. If the wedge lobe now removed the inherent resiliency of the ring will contract the right-hand end, so that the ring will appear substantially as in Fig. 5. In that condition the inner ring may be assembled with the outer ring and balls and the bearing is then complete.

When it is desired to apply the bearing to a shaft the contracted bore is expanded'by any suitable tool or wedge, such as the wedge H5 or a screw driver type of wedge, which maybe driven into the-slot I3 'to a sufficient extent to expand the ring and permit the same to he slid along on the shaft to the desiredposition. When theexpanding toolis removed the expanded end of the ring will contract on the shaft and .hold

the ring with the desired security, determined by the design ofthe bearing, as heretoforenoted. .It will be seen that by my improved means and method theinner bearing ring is securely held on the shaft concentrically. The security with which the ring is'held may be made substantially equal to that of a press fit and yet the bearing may be very readily applied to or removed from the shaft withoutthe aid of a press, and therefore the bearing is readilyapplicable to shafts where a press is not available nor its use practicable. There are not parts to become loosened or to become lost.

While I have illustrated my invention in an inner bearing ring in which only one end of the ring is expansible, it will be clear that other embodiments inboth inner and outer rings may be made and other parts of the ring may be rendered expansible; for example, both ends "of the ring may be provided with slots or the like to render the same expansible.

While I prefer to provide a pair of diametrically opposite slots in the ring, since that method provides a proper concentric relationship of the inner ring and the shaft, it is to be observed that in some cases a single slot will suffice and, furthermore, if a pluralitycf slots-be employed they may be arranged as desired, whether or not diametrically opposite.

It will furthermore be clear that the bore need not be formed as herein specifically described and it may be provided with one or more lands or projections to, in effect, bite into the shaft for more securely holding the inner ring against turning or against endwise movement on the shaft.

While the invention has been described in considerable detail and one preferred form illustrated, it is to be understood that various changes and modifications, some of which have been herein indicated, may be made within the scope of the invention as defined in the appended claims.

I claim:

1. The method of treating the inner ring of an anti-friction bearing so as toprovide means for resiliently and frictionally engaging a shaft, which comprises slitting one end of said iImer ring-so as to render thebore of the ring at that end expansible radially, then radially expanding the expansible end of said ring, then removing material from the bore of said ring at the unexp'a'nded' portion thereof, "and then releasing the expanding force, forthe purpose described.

2. The method of treating theinner'ring of an anti friction bearing'so as top'rovide'means for resiliently engagin'g'the same "With'a shaft,

which comprises forming a bore of substantially uniformdiameter through'said inner ring, slitting one end of said inner ring to render the bore at'that end expansible radially, expanding thebore in the slitted'end of "said ring and then removing metal 'from the entire bore'to provide a substantially uniform diameter bore while the slitted end is expanded, and then releasing the expanding 'force, 'for the purpose described.

RAYMOND R. SEARLES. 

